RESULTS: LAB strains with good β-glucosidase activity were isolated from fermented tofu. Their bioconversion of flax lignan extract was investigated by resting cell catalysis and microbial fermentation, and the metabolism of SDG by Lactiplantibacillus plantarum C5 following fermentation was characterized by widely targeted metabolomics. Five L. plantarum strains producing β-glucosidase with broad substrate specificity were isolated and identified, and they all can transform SDG into secoisolariciresinol (SECO). L. plantarum C5 resting cell reached a maximum SDG conversion of 49.19 ± 3.75%, and SECO generation of 21.49 ± 1.32% (0.215 ± 0.013 mm) at an SDG substrate concentration of 1 mM and 0.477 ± 0.003 mm SECO was produced at 4 mm within 24 h. Although sixteen flax lignan metabolites were identified following the fermentation of SDG extract by L. plantarum C5, among them, four were produced following the fermentation: SECO, demethyl-SECO, demethyl-dehydroxy-SECO and isolariciresinol. Moreover, seven lignans increased significantly.
CONCLUSIONS: Fermentation significantly increased the profile and level of flax lignan metabolites, and the resting cell catalysis benefits from higher bioconversion efficiency and more straightforward product separation. Resting cell catalysis and microbial fermentation of flax lignan extract by the isolated β-glucosidase production L. plantarum could be potentially applied in preparing flax lignan ingredients and fermented flaxseed. © 2024 Society of Chemical Industry.
结果:从发酵豆腐中分离出具有良好β-葡萄糖苷酶活性的LAB菌株。通过静息细胞催化和微生物发酵研究了亚麻木酚素提取物的生物转化,植物乳杆菌C5发酵后对SDG的代谢具有广泛靶向的代谢组学特征。分离并鉴定了5株产生具有广泛底物特异性的β-葡萄糖苷酶的植物乳杆菌菌株,它们都可以将可持续发展目标转化为塞科isolariciresinol(SECO)。植物乳杆菌C5静息细胞达到49.19±3.75%的最大SDG转化率,在SDG底物浓度为1mM和0.477±0.003mm的情况下,SECO产生量为21.49±1.32%(0.215±0.013mm),在24小时内以4mm的速度产生SECO。尽管植物乳杆菌C5发酵SDG提取物后鉴定出16种亚麻木酚素代谢产物,其中,发酵后产生了四个:SECO,去甲基-SECO,去甲基-去羟基-SECO和异丙烯醇。此外,7种木脂素显著增加。
结论:发酵显著增加了亚麻木酚素代谢产物的分布和水平,和静止细胞催化受益于更高的生物转化效率和更直接的产物分离。分离的β-葡萄糖苷酶生产植物乳杆菌对亚麻木酚素提取物的静息细胞催化和微生物发酵可用于制备亚麻木酚素成分和发酵亚麻籽。©2024化学工业学会。